October 5, 2017

Abrupt Stoppage

Originally published March 24, 2008
image by Hold Siegfried, St. Marein, Austria

I like this image for two reasons. First, it was taken with a schiefspiegler telescope, an exotic multiple mirror telescope that I had an unconsummated passion for 40 years ago. Although schiefspieglers are rare in the US, apparently a number have been built in Europe and Hold's image (originally posted on the LPOD Photo Gallery) is the first I've seen from one of these legendary telescopes. The second reason I like the image is that it shows a neat area of the Moon, where a lot has happened. It is the border of Mare Nubium and the southern highlands. The floor-fractured crater Pitatus is at upper right, with the ring within a ring concentric crater Hesiodus A to its left. Striking at an angle that isn't concentric or radial to any nearby basin is the Hesiodus Rille. This is a typical U-shaped rille with a sunken floor bounded by two scarps. I hadn't realized that the rille stops dead in Palus Epidemiarum, and don't know why it does so. But notice that it also just stops at its eastern end too, hmm. The three well known domes in Capuanus are clearly visible-they always seem very difficult to see at the eyepiece.